In an age when journalists have, in large numbers, moved from the bullshit-detection business to the bullshit-promulgation business, it's always welcome to come upon a book that hoists its flag proudly in the first camp. Eliane Glaser's is one such.

Her central idea is that we need to revive the good old Marxist notion of false consciousness, and quick. The freer we seem to be, the less free we are. Real disparities of class and power are obscured by blather about opportunity and aspiration. Real arguments are sidestepped by the reluctance of politicians to draw overt ideological lines in the sand. The rhetoric of bottom-up reform, people-power and choice masks gross abdications of top-down responsibility. "Christians!" our Neros are saying: "We're pioneering a new system of lion self-regulation and empowering you to live the dream of a progressive Christian/Lion stakeholder partnership!"

Glaser, let it be said, is not wrong, and she sets about to cover a huge sweep of territory: from beyond-left-and-right managerialism in political rhetoric, through astroturfing and greenwashing, techno-utopianism, food politics, gender politics, modern attitudes to science, the change in western workplace culture … All modern life is here, and on fast-forward. The sheer range, alas, means that much comes second-hand. The theoretical work has mostly been done, as she acknowledges, by the likes of Marx, Adorno and Bourdieu. The practical – ie journalistic – work has, again as she acknowledges with generous quotation, also largely been done by others such as Naomi Klein, George Monbiot, Nick Davies or Felicity Lawrence.

Glaser herself is more theorist than reporter. When a piece of pathetic Coca-Cola greenwashing (the trumpeted launch of the Plantbottle, with promises to produce 2bn – of, ahem, an annual 580bn – pop bottles out of 15 to 30% plant-based material) was applauded as "a revolutionary solution" by an organisation called the Climate Group, Glaser writes: "This seemed to me to be something of an overstatement, so I did a bit of digging to try to work out just how green the Climate Group really is." Her "digging", at least from the evidence she presents, consisted of looking it up on Wikipedia, googling some cuts and then concluding: "It was pretty hard to find out." Heigh ho: on to the next thing.

The advertised virtue of this book is its sceptical rigour. I'm afraid it doesn't live up to its promises. Rather, like a TV talent show promoting the idea of social mobility, Get Real promotes the idea of scepticism but doesn't do much to promote a method. We're told ex cathedra that rules banning alcohol on the tube "appeal to an imaginary generalised will, but are basically just there so that Boris's ilk can enjoy a civilised commute home free from the beer-swilling rabble, before popping open the prosecco in the privacy of their own dining rooms". The evidence she provides that Coalition public-spending cuts "were indeed driven by a rightwing ideological intent" is that "you could see that in the enthusiasm with which cheering Tory back-benchers waved their order papers".

At the higher level the same obeisance to received ideas is in evidence. Lacan gets a free pass apparently because (via that old wife-strangler Louis Althusser) he is congenial to the author's outlook. Glaser is rightly sceptical of the claims made (usually by journalists rather than neuroscientists) for neuroscience and brain imaging – but it couldn't hurt to admit that buying into Lacan's "Mirror Stage" involves some fairly tenuous leaps from the observational data. The rightness of Freud's three-part psychoanalytic scheme, likewise, is assumed – although Glaser, unlike proper Freudians including Freud himself, uses "subconscious" and "unconscious" interchangeably.

Small sloppinesses are common. "Machinima" isn't a "computer programme" but a genre. Derrida wasn't a literary critic. Gramsci, Althusser and Adorno weren't "post-modernists". Pulp Fiction and Reservoir Dogscan hardly be said to be presenting themselves as "realer-than-thou": both are highly stylised and fourth-wall-breaking films.

The bigger problem is Glaser's broad-brush thinking. It often elides potentially interesting distinctions. The internet, for instance, in one of the weakest chapters, is treated as a monolithic object. Yes, be sceptical about all that Web 2.0 baloney about people-power: but note too that Google's way of monetising the web and Apple's walled-garden model are different in interesting ways. Not all evil corporations have the same evil plan. It doesn't do to write off computer games – in implied contradistinction to traditional artistic productions – as "a sterile metal-and-plastic box", or harrumph: "Interactive games are becoming so popular in museums that children soon won't tolerate learning anything unless it involves touch-screen technology."

That sort of overcooked generalisation abounds. "Web 2.0 evangelism risks erasing centuries of human civilisation and returning us to the dark ages," she writes. Really? Immersive TV "underestimates viewers' rationality and helps screens take over our lives". Really? She even finds it in her heart to be outraged about Compare the Meerkat, complaining that it's "more pernicious than a straightforward insurance-comparison site, because it's providing recreation, not cynically selling".

And how are we to begin to unpack a sentence like this: "I'll be arguing that science should be a tool for overt ideologies, a way of enabling us to achieve democratically agreed ideals." Particularly in a book where the author is arguing that material inequities are obscured by the language of aspiration, and that people are hoodwinked into voting for the wrong things, it's a bit of a snake eating its tail. Which ideals? Democratic how? And should science be "a tool"? It's not always clear the author knows exactly what she means.

When she writes: "The Nasdaq crash of 2001 seems not to have dented the enthusiasm of cyber-utopians today," that's a non-sequitur: the over-valuation of dotcom stocks a decade ago is one issue; the transformative potential of any and all electronic technologies is another. Of Antony Gormley's "One & Other" – where a succession of ordinary people got to spend an hour on the empty plinth in Trafalgar Square – she reports disappointedly: "There was relatively little nudity, public defecation or other evidence of iconoclastic rebellion." Well. Those things are nice and fun, obviously – but they're hardly the infallible signs of someone Sticking It to the Man.

And for all her talk of busting taboos, there is very little here that will come as a surprise to a moderately attentive reader of this newspaper. The Tea Party isn't a genuinely grassroots movement. Supermarkets and political parties offer the illusion of choice but resist supplying the information that makes those choices meaningful. TV presents fantasies of overnight success as a sop to those suffering real socioeconomic disadvantage. Jamie Oliver doesn't dig his own carrots. Avatar doesn't present a realistic plan for saving the planet from global warming. David Cameron is a millionaire.

Glaser is caught in a classic High-Table liberal bind: she believes in power to the people but has a pretty low opinion of the average person's ability to tell the difference between Hollywood films and real life. Again and again she overstates, telling us how "we" are hoodwinked in ways that only the author and a select few are able to decode. More often than seems necessary – and rather against the grain of her thesis – she personalises her argument. "I've long been a fan of Nigel Slater," she confides. "I'm fine with Heston Blumenthal," she reassures us. "I am tired of" X, she writes. "I smell a rat" about Y. "I am heartily sick" of Z.

I feel as if I'm being meaner than really I want to. I'm broadly on Glaser's side. Get Real is unexceptionable in its broad outline – and sprinkled with interesting nuggets of fact. Glaser is dead on about the way that corporate interests co-opt resistance, that the illusion of choice comes to substitute for the real thing, and that various apparently progressive positions – from neo-Darwinian science to the natural birth movement – can subtly downgrade the idea of human agency and serve sneakingly conservative agendas. But there's clearer writing and clearer thinking on these subjects to be found elsewhere.